4-methylsulfonyloxyphenyl-N-methylthiolcarbamate (hereinafter abbreviated to "compound A"), one of the effective components of the present invention is a known compound described in Japanese patent application Kokai (Laid-Open) No. 47527/78. This compound has a broad antimicrobial spectrum and is effective in controlling various soil borne plant diseases on crops and turfs, caused by Fusarium sp., Pythium sp., Rhizopous sp., Phytophthora sp., Trichoderma sp., Rhizoctonia sp., Corticium sp. and the like. However, a sufficient fungicidal effect cannot always be obtained.
1-isopropylcarbamoyl-3-(3,5-dichlorophenyl) hydantion (hereinafter abbreviated to "compound B") is a known compound described in Japanese patent application Kokai (Laid-Open) No. 8097/72, and is developing as a fungicide for controlling gray mold, stem rot and the like. Though compound B is effective against the soil borne plant diseases, caused by Trichoderma sp., Rhizopus sp., Rhizoctonia sp., Fusarium sp., Helmintsporium sp., ; Puccinia sp., sufficient controlling effect cannot be obtained when compound B is used at such a low concentration as to be nonphytotoxic to crops and turfs.